also vice president joe biden and his family greeted supporters at the latino inaugural party. >> hundreds of thousands are gathering on the national mall to see history being made. >> and while officials say right now there is no credible threat, security, as you can imagine, is once again extremely tight. >> reporter: they will be everywhere, snipers dotting roof tops, the coast guard patrolling waterways, military fighter jets enforcing a no-fly zone. 13,000 security personnel blanketing the washington mall. >> protecting an event this large, this complex with this number of people coming requires a lot of coordination and a lot of organization. >> reporter: all coordinating here. the multiagency communications center overseen by the secret service at an undisclosed location. they'll monitor surveillance images and potential threats. the 2009 inauguration was a logistical nightmare, hundreds of ticketholders getting stuck in this tunnel. authorities say this time it will be better. >> there will be such a different feel when you come down this time for the inauguration. there is extensi